Purists preach that to properly prepare for the cycling season, you need to roll out six weeks ahead and do nothing but low-heart-rate, low-intensity rides before you throw the hammer down and go out and play, especially if your idea of fun is a frisky group ride. It's no problem if you're a Discovery rider with nothing but time and a salary to ride, but for the rest of us, it's precious pedal time we simply don't have. Thankfully, it's also unnecessary.

"For pros who can ride 20 to 30 hours a week, a long base training period is appropriate," says expert coach Jeb Stewart, C.S.C.S., owner of the online coaching company Endurofit. "But if you struggle to squeeze in half that amount, it's almost counterproductive because you aren't clocking enough saddle time to elicit a training stress." Stress is key. If you don't have hours to slowly tax your system, you need to do shorter rides with focused efforts to stimulate fitness adaptations, says Stewart. "You can get the same amount of training stress in a 90-minute tempo interval workout as you can in a three-hour endurance ride."

You'll still need to build in saddle time to condition your body to sit on a bike for longer rides, but Stewart's focused four-week plan will lay down a solid fitness foundation for the season ahead. To stave off early-season aches and pains, warm up and cool down before and after each workout, and recover for five minutes between intervals.

Fast Pedaling: Spin quickly with proper form (see What's In It). Active and recovery periods are the same duration. Improves pedaling efficiency and increases workout intensity.

Big Gear Tempo: Ride a bigger gear at a specified cadence in the Tempo zone. (If knees begin to hurt, decrease the gear and increase the cadence to do regular tempo work instead.) Improves muscular endurance and increases training stress.

Endurance: Ride for two to five hours in the Endurance zone at a comfortably high cadence. Boosts muscular endurance, aerobic fitness and fat-burning capacity.

Hills: Ride in the Endurance and Tempo zones on hilly terrain using gearing and cadence to control effort. Improves muscular endurance and overall strength.

HR Zones and T PowerThreshold heart rate (hr): Average HR or power for a 20-minute time trial or 1-hour hard group rideThreshold Power: Average power for a 20-min. time trial minus 5% of this numberThreshold (T): 95-105% of T HR/91-105% of T powerActive Recovery: <68% of T HR/<55% of T powerEndurance: 69-83% of T HR/56?75% of T powerTempo: 84-94% of T HR/76?90% of T power